"Taping joints in hardie board," in the Ceramic and Stone Q&A forum, begins: "How crucial is it? I have a couple of 20x20 areas in my home. Alpha brick pavers going down. Two ..."

Taping joints in hardie board

How crucial is it? I have a couple of 20x20 areas in my home. Alpha brick pavers going down. Two different tile guys have told me to skip it. In another thread it was mentioned that the joints showed through after they were taped and Stullis called it a rookie mistake. This would be the first I've used the tape. I know they are supposed to be taped but that won't help me if they show through. How difficult is it to keep from making humps? Thanks.

Hardi is one cbu that you don't want to skip this step. Because of it's composition Hardi is more prone to movement at the joints than other CBU's. It's also not as easy to get the taped joints as flat.

Taper the mud out several inches from the joint , sand it off smooth after it dries, but don't skip that step altogether.

If you haven't already bought or installed the Hardi, try using Permabase. The edges are tapered to allow for tape and mud. Much easier to work with.

Thanks for the replies guys. The hardie is already down. Is this a one step process? Can I put it down with the flat side of a trowell or should I put it down with the narrow end of the trowell and come back the next day with the wide flat side? These pavers are pretty forgiving, but I would not want to see 3x5 sheets telegraghing through. I'll try to get some pics next week if you promise not to laugh.

Ok, I spent last week and got all the pavers stuck. Next I will seal and grout. The tape the supply house sold me was self sticking although I did not know that untill I opened it. Quick and easy to put down but I have trouble believing it could possibly be adding any strength to the joints, but it was cheap and quick, so what the heck.

The floor was in terrible shape. This is not something I would normally take on for a custumer. What tile I do is almost always on a slab. I used 1/2 '' hardieboard so I could shoot it down with ring shank nails after modified thinset. I would blow through 1/4 ''. I have tried to use the screws in the past and have always made an absolute mess with them. This may not be ideal,but it is the best I could come up with.

In my pre-Ditra years I used a framing nailer for Hardi, but it wasn't a clipped-head nailer like that one, it was a coil nailer. The problem with those nails, and even the full-head nails to some degree, is that they tend to blow partway through the board. The key is to watch the pressure on the compressor, and of course you should avoid the joists since you're using a nail that length.

Since yours is done, there's nothing you can do except make sure the board is secure. If you see any vertical movement indicating the nail has blown through, you'll want to add some nails.

It's difficult, if not impossible, to find roofing nails that are hot-dipped galvanized that can be used in a roofing nailer.

The hardie has actually been down at least a couple months while I worked on some other things but it seems solid as a rock so far. I will use ditra for the first time in a couple of weeks on a charity job at a church in a blighted neighborhood where the material has been donated and I will furnish the install. Seems like a good one to learn on.

Here's some pics. Sorry they are a little late. Wife was happy with the new floor

. She came to me laughing and said," I was cooking tacos and dropped some meat on the floor and now I can't find it." She had 9 girls down for the labor day weekend and being the good husband I went down to help.